Many projects designed to reduce carbon emissions focus on reducing the rate of deforestation or on replanting of forests that were harvested in the past. In yesterday's PLoS Biology Jack ("Francis") Putz and his colleagues point out that following improved forest practices can also have a very large effectt. Specifically, by adopting practices associated with reduced impact logging in tropical forests (planning of log landings, planning of roads, construction of bridges and water culverts, planning of skid trails, marking of future crop trees, directional felling, and liana cutting) the authors estimate that carbon emissions could be reduced by 0.16 gigatons per year.

To put that in perspective, total CO2 emissions in 2005 were 28.2 gigatons. A reduction of 0.16 gigatons per year would make that an even 28 gigatons, a reduction of about about 0.7%. That may not sound like a lot, but consider this. During the 1990s ttopical deforestation was responsible for about 1.5 gigatons of CO2 emissions annually (source). A reduction of 0.16 gigatons would represent about 10% of the total emissions associated with tropical deforestation. Suppose we could reduce deforestation rates by 50% by 2050, the annual reduction in CO2 emissions would be about 0.5 gigatons.1 Now reduced impact logging is looking very promising. It would eliminate almost 1/3 as much CO2 as an ambitious program to reduce deforestation. Better yet, if we combined a 50% reduction in deforestation with reduced impact logging, the total annual savings would climb to 2/3 of a gigaton, or over 15% of the total reduction in CO2 emissions necessary to stabilize atmospheric concentrations at 450ppm.2

1The Gullison et al. paper in Science estimates a total of 50 gigatons over the 21st century. I get 0.5 gigatons per year by dividing 50 by 100.2Here's how I get the "over 15%". Gullison et al. say that 50 gigatons is about 12% of the total needed. If 50 reduced impact logging adds 1/3 to that, the total reductions become 16%.

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Welcome to the seventh edition of Berry Go Round, the carnival about all things botanical. The previous edition was last month at Seeds Aside and the 8th issue will be at the end of August on Not Exactly Rocket Science.... Read More